Add a nextboot manual page.

Spotted by:	brandt@fokus.gmd.de

sbin/reboot/nextboot.8

@@ -0,0 +1,116 @@
+.\" Copyright (c) 2002 Gordon Tetlow
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.\" Note: The date here should be updated whenever a non-trivial
+.\" change is made to the manual page.
+.Dd November 4, 2002
+.Dt NEXTBOOT 8
+.Os
+.Sh NAME
+.Nm nextboot
+.Nd specify an alternate kernel and boot flags for the next reboot
+.Sh SYNOPSIS
+.Nm
+.Op Fl f
+.Op Fl o Ar options
+.Fl k Ar kernel
+.Nm
+.Fl D
+.Sh DESCRIPTION
+The
+.Nm
+utility allows specifying an alernate kernel and/or boot flags for the
+next time the machine is booted. Once the loader loads in the new kernel
+information, it is deleted so in case the new kernel hangs the machine,
+once it is rebooted, the machine will automatically revert to it's previous
+configuration.
+.Pp
+The options are as follows:
+.Bl -tag -width ".Fl o Ar options"
+.It Fl D
+Invoking
+.Nm
+with the
+.Fl D
+option removes an existing nextboot configuration
+.It Fl f
+The
+.Fl f
+option disables the sanity checking which checks if the kernel really exists
+before writing the nextboot configuration.
+.It Fl k Ar kernel
+The
+.Fl k
+option with required kernel argument specifies a kernel directory relative to
+.Pa /boot
+to load the kernel and any modules from.
+.It Fl o Ar options
+The
+.Fl o
+allows the passing of kernel flags for the nextboot.
+.El
+.Sh FILES
+.Bl -tag -width ".Pa /boot/nextboot.conf" -compact
+.It Pa /boot/nextboot.conf
+The configuration file that the nextboot configuration is written into.
+.El
+.Sh EXAMPLES
+To boot the GENERIC kernel with the
+.Nm
+command:
+.Pp
+.Dl "nextboot -k GENERIC"
+.Pp
+To enable into single user mode with the normal kernel:
+.Pp
+.Dl "nextboot -o ""-s"" -k kernel"
+.Pp
+To remove an existing nextboot configuration:
+.Pp
+.Dl "nextboot -D"
+.Sh SEE ALSO
+.Xr boot 8 ,
+.Xr loader 8
+.Sh HISTORY
+The original
+.Nm
+manual page first appeared in
+.Fx 2.2 .
+It used a very different interface to achieve similar results.
+.Pp
+The current incarnation of
+.Nm
+appeared in
+.Fx 5.0 .
+.Sh AUTHORS
+This manual page was written by
+.An Gordon Tetlow Aq gordon@FreeBSD.org .
+.Sh BUGS
+The nextboot code is implemented in the loader. It is not the most throughly
+tested code. It is also my first attempt to write in Forth.
+.Pp
+Finally, it does some evil things like writing to the filesystem before it
+has been checked. If it scrambles your filesystem, don't blame me.